Detergent compositions containing oligomeric ester chain condensates of ethane-1-hydroxy-1,1-diphosphonic acid as builders

ABSTRACT

BUILT DETERGENT COMPOSITIONS CONTAINING AN ORGANIC SYNTHETIC DETERGENT AND A BUILDER WHICH IS AN OLIGOMERIC ESTER CHAIN CONDENSATE OF ETHANE-1-HYDROXY-1,1-DIPHOSPHONIC ACID IN A PROPORTION OF DETERGENT TO BUILDER OF 5:1 TO ABOUT 1:20, BY WEIGHT.

United States Patent O 3,562,169 DETERGENT COMPOSITIONS CONTAINING OLI-GOMERIC ESTER CHAIN CONDENSATES OF ETHANE 1 HY DROXY 1,1 DIPHOSIHONICACID AS BUILDERS James B. Prentice, Batesville, Ind., assignor to TheProcter & Gamble Company, Cincinnati, Ohio, a corporation of Ohio NoDrawing. Filed Dec. 23, 1968, Ser. No. 786,372 Int. Cl. Clld 3/36 US.Cl. 252-152 5 Claims ABSTRACT OF THE DISCLOSURE Built detergentcompositions containing an organic syn thetic detergent and a builderwhich is an oligomeric ester chain condensate ofethane-l-hydroxy-l,l-diphosphonic acid in a proportion of detergent tobuilder of 5:1 to about 1:20, by weight.

FIELD OF THE INVENTION This invention relates to build detergentcompositions which are especially useful in household laundrysituations. Built detergent compositions have many uses, however,including dishwashing and other household washing and cleaningapplications such as washing soiled walls and floors.

The use of builder compounds as adjuncts to soap and syntheticdetergents is widespread. The property of some materials to improve thecleaning levels of detergent compounds is a well-known phenomenon. Notwithstanding the fact that this property is widely appreciated in theprior art, the exact behavior and mechanics of how builders perform andfunction still are not fully understood. A set of criteria does notexist which would permit one to predict which compounds possesssignificant builder properties.

Builder compounds are thought to have some effect on such diverseaspects of detergency as stabilization of soil suspension,emulsification of soil particles, the surface activity of aqueoussolutions, foaming or suds-producing characteristics of washingsolutions, peptization of soil agglomerates, neutralization of acidsoil, and the inactivation of mineral constituents present in thewashing solution (so-called sequestering or water softening). This listis not exclusive since other described properties of builder compoundsare known. The point is that no general basis has been found either asregards physical properties or chemical structure by which one mightwith certainty predict the suitability of chemical materials as buildersfor detergent compositions.

The known compounds which have been found useful as builders can bedescribed as being of the classes of inorganic and organic alkalinebuilder salts. An example of the inorganic type is sodiumtripolyphosphate which is perhaps the most widely known and commerciallyused builder. Other examples of inorganic alkaline builder salts aresodium pyrophosphate which is also commercially used as well as otheralkali metal carbonates, borates, phosphates, silicates and the like.

Alkali metal salts of nitrilotriacetic acid, ethylenediaminetetraaceticacid, ethane-l-hydroxy 1,1 diphosphonic acid, and ethane-l-hydroxy 1,1,2triphosphonic acid are examples of known organic alkaline builders.

It is common to employ mixtures of such organic and inorganic compoundsin commercially available built detergent compositions. Each of theknown builder compounds in both the inorganic and organic classes havecertain advantages and disadvantages. The need for and interest inproviding suitable alternatives and replacements ICQ for known buildersunderscores continued research and development for improved buildercompounds.

SUMMARY OF THE INVENTION This invention relates to a new class oforganophosphorus compounds which are oligomeric ester chain condensatesof ethane-l-hydroxy-l,l-diphosphonic acid. More especially, it relatesto the use of such materials in combination with organic syntheticdetergents to provide effective built detergent compositions. Theoligomeric ester chain condensates which are useful in the presentinvention are believed to be heretofore unknown materials. For thisreason, they are the subject of a copending, commonly assigned patentapplication Ser. No. 786,371 filed Dec. 23, 1968 which is beingconcurrently filed with the present application by James B. Prentice asOligomeric Ester Chain Condensates of Ethane 1 Hydroxy-1,1-DiphosphonicAcid. Although condensates of ethane-1- hydroxy-1,1-diphosphonic acidhave been previously known, such as those described in US. Pat.3,387,024 and US. Pat. 3,400,151, it is believed that the oligomericester chain condensates described herein are the first condensates whichcontain ester bonds, C-OP bonds.

It is a primary object of this invention to provide a 5 new and improvedclass of builder compounds which are oligomeric ester chain condensatesof ethane-l-hydroxy- 1,1-diphosphonic acid. The present inventionpertains to detergent compositions comprising a water-soluble organicsynthetic detergent and a builder selected from the newly discoveredclass of builder compounds described herein.

DETAILED DESCRIPTION OF THE INVENTION l P OiM2 OM CH3 wherein each M ishydrogen, alkali metal, ammonium, alkylammonium, hydroxyalkyl ammonium,amine, alkylamine, or hydroxyalkylamine; the alkyl and hydroxyalkylgroup each having from 1 to about 4 carbons; R is hydrogen or acetyl;and n has a numerical value in the range of l to about 16, theproportion of said detergent to said builder being in the range of fromabout 5 :1 to about 1:20, by weight. Preferably, the proportion of saidorganic detergent to the oligomeric ester builder should be in the rangeof from about 2:1 to about 1:10.

In the preceding formula, suitable alkali metals are sodium, posassiumand lithium. Illustrative examples of alkyl ammonium cations aremonomethylammoniurn, diethylammonium, tripropylammonium, andtetrabutylammonium. Illustrative examples of hydroxyalkylammoniumcations are hydroxymethylammonium, hydroxyethylammonium, 2hydroxypropylammonium, and 2 hydroxybutylammonium. Illustrative examplesof alkylamine are mono-, di-, and trialkylamines including methylamine,diethylamine, and tripropylamine. Illustrative examples ofmono(hydroxymethyl)amine are di(hydroxymethyl) amine,tri(hydroxyethyl)amine.

The numerical value for n is preferably in the range of 2 to 12. Due tothe complex nature of the oligomeric ester chain condensate, it isdifficult to determine exact values for n. This point is discussedbelow.

Fully neutralized as well as partially neutralized salts arecontemplated. As described below, such salts can be prepared by merelyneutralizing the acid with an appropriate base compound.

The novel builder compounds can be prepared by any satisfactory process.One satisfactory method is that described in detail in the copendingpatent application referred to above. That copending patent applicationis incorporated herein by reference.

The process involves a reaction between phosphorous acid and aceticanhydride. The molar proportion of these reactants should be in therange of from about 1:3 to about 1:20, phosphorous acid to aceticanhydride. An excess of the acetic anhydride has been discovered toenhance the recovery of the oligomeric ester. The oligomeric ester chaincondensate formed by the reaction is insoluble in acetic anhydride andtherefore readily precipitates out of solution. Recovery is therebyenhanced. Molar proportions in excess of 1:20 phosphorous acid to aceticanhydride can be used but without any apparent advantage.

This reaction can be controlled to prepare oligomeric esters whichcontain monomeric units in the lower range of the numerical value givenabove for n or, alternatively, to prepare oligomeric esters containingmonomeric units in the upper portion of the range from 1 to 16. In anycase, the reaction product comprises a mixture of condensates havingdifferent chain lengths. Moreover, it is highly improbable that anymolecular weight determination can be obtained with desired preciseness.For this reason, the value for 'n is an estimate determined by applyingthe best and most accurate analytical means available. The means forcontrolling this reaction is described more fully below.

The reaction temperature is in the range of about C. to about 80 C.Depending upon whether short chain condensates or longer chaincondensates are desired, the temperature should be adjusted as explainedbelow. The reaction generally takes from 5 minutes to about 48 hours.Again, the duration of the reaction must take into consideration thetemperature at which the reaction is run and whether shorter or longerchain condensates are desired.

By operating with the above-prescribed reaction conditions, it ispossible to control the reaction product which is prepared. For example,by running the reaction at a temperature of about 40 C. for about 30minutes or about 5 minutes at 80 C., cooling the reaction mixture to atemperature in the range of from about 0 C. to about 30 C. and digestingthe reaction mixture at these lower temperatures for about 30 minutes toabout 48 hours, a precipitate form which is a relatively longer chainoligomeric esters of ethane-l-hydroxy-l,l-diphosphonic acid. There is nolimit to the length of the digestion period. Periods longer than 48hours can be used if found necessary to precipitate the ester. Thisagain will depend to a large extent upon the reaction temperatureemployed.

In another process embodiment when the reaction tem perature is held atabout 60 C. a precipitate begins to form within about 20 minutes. Underthese conditions, the oligomeric ester chain condensate ofethane-l-hydroxy-l, l-diphosphonic acid formed contains relatively fewermonomeric units of ethane-l-hydroxy-l,l-diphosphonic acid.

The reaction product under the prescribed conditions is comprised of amixture of oligomeric esters having from 2 to about 16 monomeric units.Depending upon the reaction conditions, the reaction product representsa mixture of oligomeric esters. Factors which are involved and whichdetermine the composition of the reaction mixture are the insolubilityof the condensate in the reaction medium which hinders growth of longchains and the degradative effects of acetic acid which tends,especially at higher temperatures, to break down the oligomeric ester toother undesired by-products.

The compounds of the present invention are the only condensates ofethane-l-hydroxy-l,l-diphosphonic acid which are known to contain amixed anhydride (COP) bond. The oligomeric ester chain condensates ofthis invention are unstable in the reaction mixture, and it is for thisreason that a solvent is employed to terminate the reaction with theformation of the desired chain condensates. In the preceding discussionit has been pointed out that a large excess of acetic anhydride shouldbe used. The reason for this is that the acetic anhydride is a suitablesolvent for the reaction and, at the same time, the oligomeric esterchain condensates are insoluble in acetic anhydride. As a result, thedesired oligomeric esters precipitate out of solution and can readily berecovered.

The stoichiometry of the reaction between phosphorous acid and aceticacid anhydride is 1:1 on a molar basis.

The precipitate which forms during the reaction is an amorphous solidreaction product.

The P MR spectra for the oligomeric ester chain condensates of thisinvention display multiplet centered at A=-15 to -16 parts per million.This MR spectra eliminates the prospect of a P-OP bonded condensate.

The possibility of branching along the chain is probable but only to alimited extent. For this reason, the oligomeric esters have at timesbeen previously referred to as primarily chain condensates.

The carbon at the end of the chain condensate can contain either ahydroxyl group or an acetyl group as noted in the general formula givenabove.

As noted above, the oligomeric ester chain condensates ofethane-Lhydroxy-l,l-diphosphonic acid of the present invention aredistinguished from previously known condensates in at least two ways.The first is the presence of a mixed anhydride bond (i.e., a C-O-Prather than a CO-C or PO-P bond). Secondly, the compounds of the presentinvention are the only known condensates of ethane l hydroxy 1,1diphosphonic acid which are larger than a dimer.

One of the major concerns in practicing the reaction described above isthe formation of acetic acid as a natural by-product when aceticanhydride is reacted with phosphorous acid. The acetic acid canextensively degrade the desired oligomeric ester chain condensates. Itcan be appreciated that higher acetic anhydride ratios are desirable inorder to force out of solution the desired oligomeric ester chaincondensates and, by the same token, higher acetic acid anhydride ratiosdilute and therefore reduce the detrimental acetic acid attack. Thereaction conditions should be chosen which best reduce acetic acidattack. Two Ways of doing this as mentioned above is by lowering thereaction temperature and by diluting the acetic acid. An alternative waywould be by adding ketone to an acetic anhydride phosphorus reactionmixture which would react with the acetic acid formed from the reactionto make acetic anhydride.

The molecular weights of the builder compounds of the present inventionare in the range of from about 500 to about 4000 calculated as thesodium salts. Within the preferred range, the molecular Weights arewithin a range of about 700 to about 3000. These values are related tothe numerical values of it presented above.

The following examples are presented to demonstrate a method forpreparing the builder compounds which are an essential part of thepresent invention.

Example I Phosphorous acid (416 g., 5.0 moles) was dissolved in aceticanhydride (4 1., 42.4 moles) and the reaction mixture heated to C. overa 20 minute period. The reaction temperature of 50 C. was maintained for20 minutes, at which time a cooling bath was applied and the reactionmixture cooled to 22 C. White solids formed at this point. The slurrywas then digested for 20 hours, the solid product recovered byfiltration and washed free of mother liquor with ethyl ether and dried.The total yield of product was 400 g. The reaction product was comprisedof oligomeric ester chain condensation ofethane-l-hydroxy-l,l-diphosphonic acid having a molecular weight in therange of from about 500 to about 4000.

The acid product was added slowly, and with good stirring, to 280 g. ofNaHCO dissolved in 2:5 1. of Water.

The final pH of the solution was about pH 5. The clear aqueous saltsolution was then divided by fractional precipitation. Increments of anon-solvent (methanol and iso-propanol) were added and the solids formedwere filtered off before the next increment was added. A total of sixsolid fractions were obtained. Data for the six demonstration describedbelow to show the effect of average molecular weight on the propertiesof the oligomeric chain condensate of EHDP. Fraction No. 1 correspondsto Oligomer (A) and Fraction No. 6 corresponds to Oligomer (B) in thedescription below of the Swatch-Dip test. Several of these fractionsalso were used in the detergency demonstration described below.

Example II Phosphorous acid (100 g., 1.2 moles) was dissolved in aceticanhydride (1 1., 10.6 moles) and the mixture heated to 55 C. Thetemperature of 55 C. was maintained until a solid precipitate had formed(ca. 20 min.) and for an additional minutes. The slurry was cooled toroom temperature, digested 10 minutes, then filtered and washed free ofmother liquor with ethyl ether. The yield of by-product was 5 8 g. Asjudged from thin layer chromatography, this sample was similar toFraction No. 6 in Example I. It was of a shorter average chain lengththan the product of Example III.

Example III Phosphorous acid (41 g., 0.5 mole) was dissolved in aceticanhydride (400 cc., 4.2 moles) at room temperature. The clear solutionwas cooled to C. and-that temperature maintained. After 24 hours aprecipitate had formed, which was digested for days at 15 C., thenfiltered, washed free of mother liquor with ethyl ether, and dried. Theyield was 42 g. of solid product. As judged from thin layerchromatography, this product was similar to Fraction No. 1 of Example I.It was of a longer average chain length than the product of Example 11.

The water-soluble organic synthetic detergents with which the buildercompounds described herein can be used include anionic, nonionic,ampholytic and zwitterionic detergent compounds, or mixtures ofcompounds selected from these general classes of detergents. Each ofthese classes is illustrated below:

(A) Anionic soap and non-soap synthetic detergents- This class ofdetergents includes ordinary alkali metal soaps such as the sodium,potassium, ammonium and alkylolammonium salts of higher fatty acidscontaining from about 8 to about 24 carbon atoms and preferably fromabout 10 to about 20 carbon atoms. Suitable fatty acids can be obtainedfrom natural sources such as, for instance, from plant or animal esters(e.g., palm oil, coconut oil, babassu oil, soybean oil, castor oil,tallow, whale and fish oils, grease, lard, and mixtures thereof). Thefatty acids also can be synthetically prepared (e.g., by the oxidationof petroleum, or by hydrogenation of carbon monoxide by theFischer-Tropsch process). Resin acids are suitable such as rosin andthose resin acids in tall oil. Napthenic acids are also suitable. Sodiumand potassium soaps can be made by direct saponification of the fats andoils or by the neutralization of the free fatty acids which are preparedin a separate manufacturing process. Particularly useful are the sodiumand potassium salts of the mixtures of fatty acids derived from coconutoil and tallow, i.e., sodium or potassium tallow and coconut soap.

This class of detergents also includes water-soluble salts, particularlythe alkali metal salts of organic sulfuric reac tion product having intheir molecular structure an alkyl radical containing from about 8 toabout 22 carbon atoms and a sulfonic acid or sulfuric acid esterradical. (Included in the term alkyl is the alkyl portion of higher acylradicals.) Examples of this group of synthetic detergents which form apart of the preferred built detergent compositions of the presentinvention are the sodium or potassium alkyl sulfates, especially thoseobtained by sulfating the higher alcohols (C C carbon atoms) produced byreducing the glycerides of tallow or coconut oil; sodium or potassiumalkyl benzene sulfonates, in which the alkyl group contains from about 9to about 15 carbon atoms, in straight chain or branched chainconfiguration, especially those of the type described in United StatesLetters Patents Nos. 2,220,099 and 2,477,- 383; sodium alkyl glycerylether sulfonates, especially those ethers of higher alcohols derivedfrom tallow and coconut oil; sodium coconut oil fatty acid monoglyceridesulfonates and sulfates; sodium or potassium salts of sulfuric acideters of the reaction product of one mole of a higher fatty alcohol(e.g., tallow or coconut oil alcohols) and about 1 to 6 moles ofethylene oxide; sodium or potassium salts of alkyl phenol ethylene oxideether sulfate with about 1 to about 10 units of ethylene oxide permolecule and in which the alkyl radicals contains about 8 to about 12carbon atoms.

Additional examples of anionic non-soap synthetic detergents which comewithin the terms of the present invention are the reaction product offatty acids esterified with isethionic acid and neutralized with sodiumhydroxide where, for example, the fatty acids are derived from coconutoil; sodium or potassium salts of fatty acid amide or methyl tauride inwhich the fatty acids, for example, are derived from coconut oil. Otheranionic synthetic detergents of this variety are set forth in UnitedStates Letters Patents 2,486,921; 2,486,922; and 2,396,278.

Still other anionic synthetic detergents include the class designated assuccinamates. This class includes such surface active agents as disodiumN-octadecylsulfo succinamate; tetrasodium N(1,2-dicarboxyethyl)-N-octadecylsulfo-succinamate; diamyl ester ofsodium sulfosuccinic acid; dihexyl ester of sodium sulfosuccinic acid;dioctyl ester of sodium sulfosuccinic acid.

Anionic phosphate surfactants are also useful in the present invention.These are surface active materials having substantial detergentcapability in which the anionic solubilizing group connectinghydrophobic moieties is an oxy acid of phosphorus. The more commonsolubilizing groups, of course, are SO H, SO H, and CO H. Alkylphosphate esters such as (RO) PO H and ROPO H in which R represents analkyl chain contain ing from about 8 to about 20 carbon atoms areuseful.

These esters can be modified by including in the molecule from one toabout 40 alkylene oxide units, e.g., ethylene oxide units. Formulate forthese modified phosphate anionic detergents are in which R represents analkyl group containing from about 8 to 20 carbon atoms, or analkylphenyl group in which the alkyl group contains from about 8 to 20carbon atoms, and M represents a soluble cation such as hydro- 7 gen,sodium, potassium, ammonium or substituted ammonium; and in which n isan integen from 1 to about 40.

A specific anionic detergent which has also been found excellent for usein the present invention is described more fully in the US. patentapplication of Phillip F. Pilaumer and Adriaan Kessler, Ser. No. 423,364filed Jan. 4, 1965 now abandoned. This detergent comprises by Weightfrom about 30% to about 70% of Component A, from about 20% to about 70%of Component B, and from about 2% to about 15% of Component C, wherein:

(a) Said Component A is a quaternary mixture of double-bond positionalisomers of Water-soluble salts of alkene-l-sulfonic acids containingfrom about 10 to about 24 carbon atoms, said mixture of positionalisomers including by weight about 10% to about 25% of an alphabetaunsaturated isomer, about 30% to about 70% of a beta-gamma unsaturatedisomer, about 5% to about 25% of a gamma-delta unsaturated isomer, andabout 5% to about of a delta-epsilon unsaturated isomer;

(b) Said Component B is a mixture of water-soluble salts ofbifunctionally-substituted sulfur-containing saturated aliphaticcompounds containing from about 10 to about 24 carbon atoms, thefunctional units being hydroxy and sulfonate radicals and the sulfonateradical always being on the terminal carbon and the hydroxyl radicalbeing attached to a carbon atom at least two carbon atoms removed fromthe terminal carbon atoms; and

(c) Said Component C is a mixture of water-soluble salts of highly polarsaturated aliphatic compounds, each having two sulfur-containingmoieties, one of which must be a sulfonate group attached to theterminal carbon atom and the other moiety selected from the groupconsisting of sulfonate and sulfate radicals attached to a carbon atomat least two carbon atoms removed from the terminal carbon atom, saidcompounds containing from about 10 to about 24 carbon atoms.

(B) Nonionic synthetic detergents.-Nonionic synthetic detergents may bebroadly defined as compounds produced by the condensation of alkyleneoxide groups (hydrophilic in nature) with an organic hydrophobiccompound, which may be aliphatic or alkyl aromatic in nature. The lengthof the hydrophilic or polyoxyalkylene radical which is condensed withany particular hydrophobic group can be readily adjusted to yield awatersoluble compound having the desired degree of balance betweenhydrophilic and hydrophobic elements.

For example, a well known class of nonionic synthetic detergents is madeavailable on the market under the trade name of Pluronic. Thesecompounds are formed by condensing ethylene oxide with a hydrophobicbase formed by the condensation of propylene oxide with propyleneglycol. The hydrophobic portion of the molecule which, of course,exhibits water insolubility, has a molecular weight of from about 1500to 1800. The addition of polyoxyethylene radicals to this hydrophobicportion tends to increase the water solubility of the molecule as aWhole and the liquid character of the product is retained up to thepoint where polyoxyethylene content is about 50% of the total weight ofthe condensation product.

Other suitable nonionic synthetic detergents include:

(1) The polyethylene oxide condensates of alkyl phenols, e.g., thecondensation products of alkyl phenols having an alkyl group containingfrom about 6 to 12 carbon atoms in either a straight chain or branchedchain configuration, with ethylene oxide, the said ethylene oxide beingpresent in amounts equal to 5 to 25 moles of ethylene oxide per mole ofalkyl phenol. The alkyl substituent in such compounds may be derivedfrom polymerized propylene, diisobutylene, octene, or nonene, forexample.

(2) Those derived from the condensation of ethylene oxide with theproduct resulting from the reaction of propylene oxide and ethylenediamine. For example, cornpounds containing from about 40% to aboutpolyoxyethylene by weight and having a molecular weight of from about5,000 to about 11,000 resulting from the reaction of ethylene oxidegroups with a hydrophobic base constituted of the reaction product ofethylene diamine and excess propylene oxide, said base having amolecular weight of the order of 2,500 to 3,000, are satisfactory.

(3) The condensation product of aliphatic alcohols having from 8 to 22carbon atoms, in either straight chain or branched chain configuration,with ethylene oxide, e.g., a coconut alcohol-ethylene oxide condensatehaving from 5 to 30 moles of ethylene oxide per mole of coconut alcohol,the cconut alcohol fraction having from 10 to 14 carbon atoms.

(4) Nonionic detergents include nonyl phenol condensed with either about10 or about 30 moles of ethylene oxide per mole of phenol and thecondensation products of coconut alcohol with an average of either about5.5 or about 15 moles of ethylene oxide per mole of alcohol and thecondensation product of about 15 moles of ethylene oxide with one moleof tridecanol.

Other examples include dodecylphenol condensed with 12 moles of ethyleneoxide per mole of phenol; dinonylphenol condensed with 15 moles ofethylene oxide per mole of phenol; dodecyl mercaptan condensed with 10moles of ethylene oxide per mole of mercaptan; bis- (N- 2-hydroxyethyl)lauramide; nonyl phenol condensed with 20 moles of ethylene oxide permole of nonyl phenol; myristyl alcohol condensed with 10 moles ofethylene oxide per mole of myristal alcohol; lauramide condensed with 15moles of ethylene oxide per mole of lauramide; and di-isooctylphenolcondensed with 15 moles of ethylene oxide.

(5) A detergent having the formula R R R N O (amine oxide detergent)wherein R is an alkyl group containing from about 10 to about 28 carbonatoms, from 0 to about 2 hydroxy groups and from O to about 5 etherlinkages, there being at least one moiety of R which is an alkyl groupcontaining from about 10 to about 18 carbon atoms and 0 ether linkages,and each R and R are selected from the group consisting of alkylradicals and hydroxyalkyl radicals containing from 1 to about 3 carbonatoms;

Specific examples of amine oxide detergents include:

dimethyldodecylamine oxide dimethyltetradecylamine oxideethylmethyltetradecylamine oxide cetyldimethylamine oxidedimethylstearylamine oxide cetylethylpropylamine oxidediethyldodecylamine oxide diethyltetradecylamine oxidedipropyldodecylamine oxide bis- 2-hydroxyethyl dode cylamine oxidebis-(2-hydroxyethyl)-3-dodecoxy-l-hydroxypropyl amine oxide(2-hydroxypropyl)methyltetradecylamine oxide dimethyloleyamine oxidedimethyl- 2-hydroxydodecyl amine oxide and the corresponding decyl,hexadecyl and octadecyl homologs of the above compounds.

(6) A detergent having the formula R R R P 0 (phos phine oxidedetergent) wherein R is an alkyl group containing from about 10 to about28 carbon atoms, from 0 to about 2 hydroxy groups and from 0 to about 5ether linkages, there being at least one moiety of R which is an alkylgroup containing from about 10 to about 18 carbon atoms and 0 etherlinkages, and each of R and R are selected from the group consisting ofalkyl radicals and hydroxyalkyl radicals containing from 1 to about 3carbon atoms.

Specific examples of the phosphine oxide detergents include:

dimethyldodecylphosphine oxide dimethyltetradecylphosphine oxideethylmethyltetradecylphosphine oxide cetyldimethylphosphine oxidedimethylstearylphosphine oxide cetylethylpropylphosphine oxidediethyldodecylphosphine oxide diethyltetradecylphosphine oxidedipropyldodecylphosphine oxide bis- (hydroxymethyl) dodecylphosphineoxide bis- 2-hydroxyethyl dodecylphosphine oxide(Z-hydroxypropyl)methyltetradecylphosphine oxide dimethyloleylphosphineoxide, and

dimethyl- (Z-hydroxydodecyl phosphine oxide and the corresponding decyl,hexadecyl, and octadecyl homologs of the above compounds.

(7) A detergent having the formula T R -S-R=' (sulfoxide detergent)wherein R is an alkyl radical containing from about 10 to about 28carbon atoms, from 0 to about ether linkages and from 0 to about 2hydroxyl substituents at least one moiety of R being an alkyl radicalcontaining 0 ether linkages and containing from about to about 18 carbonatoms, and wherein R is an alkyl radical containing from 1 to 3 carbonatoms and from one to two hydroxyl groups.

octadecyl methyl sulfoxide dodecyl methyl sulfoxide tetradecyl methylsulfoxide 3-hydroxytridecyl methyl sulfoxide 3-methoxytridecyl methylsulfoxide 3-hydroxy-4-dodecoxybutyl methyl sulfoxide octadecyl2-hydroxyethyl sulfoxide dodecylethyl sulfoxide (C) Ampholytic syntheticdetergents.Ampholytic synthetic detergents can be broadly described asderivatives of aliphatic or aliphatic derivatives of heterocyclicsecondary and tertiary amines, in which the aliphatic radical may bestraight chain or branched and wherein one of the aliphatic substituentscontains from about 8 to 18 carbon atoms and at least one contains ananionic watersolubilizing group, e.g., carboxy, sulfo, sulfato,phosphato, or phosphono. Examples of compounds falling within thisdefinition are sodium 3-(dodecylamino)-propionate 0 Ci2 I I-CH2CH2( 3ONa sodium 3- (dodecylamino propanel-sulfonate H C 1211251 1 CN2CH2 OHzSOaWa sodium 2- (dodecylamino) ethyl sulfate H GigHgfilL'CHQCHgO S OaNasodium 2- (dimethylamino) octadecanoate 0 ClmlImCliC1126) ONa H CNCHsdisodium 3 (N-carboxymethyl-dodecylamino)propane-1- sulfonate CH2CH2CH2SOaNa o C En 0 Na disodium 2- (oleylamino ethyl phosphate 0 C 18113515CHzCIIgO 1i (ONa) 2 disodium 3-(N-methyl-hexadecylamino) propyl-l-phoshonate 1 T C1eHs5NCH2CHzCH2P(0Na)2 disodium octadecyl-iminodiacetateClBH37H (CHfl l ONa) 2 sodium l-carboxymethyI-Z-undecyl-irnidazoledisodium 2 [N (2-hydroxyethyl)octadecylamino] ethyl phosphate 1! CH2CH2OP (ONEDZ is sv CHzCHaOH and sodiumN,N-bis(Z-hydroxyethyl)-2-sulfato-3-dodecoxypropylamine OSOzNa o 2H20omofiommcmomomg (D) Zwitterionic synthetic detergents.-Zwitterionicsynthetic detergents can be broadly described as derivatives ofaliphatic quaternary ammonium and phosphonium or tertiary sulfoniumcompounds, in which the cationic atom may be part of a heterocyclicring, and in which the aliphatic radical may be straight chain orbranched, and wherein one of the aliphatic substituents contains fromabout 8 to 18 carbon atoms, and at least one aliphatic substituentcontains an anionic water-solubilizing group, e.g., carboxy, sulfo,sulfato, phosphato, or phos phono. Examples of compounds falling withinthis definition are 2-N,N-dimethyl N -heXadecyl-ammonio)-2-hydroxypropane-l-sulfonate CH3 OH CmHnNCH2( JHOH1S 03 3-(N,N-dimethyl Nhexadecylammonio)propane-l-sulfonate CH3 o16r-I33N o112o11 oms on2-(N,N-dimethyl-N-dodecylammonio)acetate E 11 C1zHg NCH2CO3-(N,N-dimethyl-N-dodecylammonio)propionate E n CrzHz N-CHgCHgC-O2-(N,N-dimethyl-N-octadecylammonio) -ethyl sulfate 2- (trimethylammonioethyl dodecylphosphonate 1 1 ethyl 3(N,N-dimethyl-N-dodecylammonio)propylphosphonate 3-(P,P -dimethyl Pdodecylphosphonio) propane-1- sulphonate ClZHQiP-CHgCIIzCHfl s 032-(S-methyl S tert hexadecyl-sulfonio)ethane 1 sulfonate 3-S-methyl-S-dodecylsulfonio -propionate CI'Ig I u e 012112568; CHzCI'IzC-0 sodium 2 (N,N dimethyl N dodecylammonio)ethyl phosphonate CH; O ONa Ill 0121125NCH1GIIQ1 e 0113 0 4-(S-methyl-S-tetradecylsulfonio)butyrate Ill 9 C 4H29eb3CH CHzCH CO 1- 2-hydroxyethyl)-2-undecyl-imidazoliuml-acetate N-oIIzoI-Izo1-I o (Iliad-o 2-(trimethylammonio -octadecanoate O owrrworr i 3o and 3-(N,N bis (2hydroxyethyl) N octodecylammonio)-2-hydroxy-propane-l-sulfonate.

CHZCH OH 018N37N-0H20H0H2S03 CH CHzOH Some of these detergents aredescribed in the following US. Pats. 2,129,264; 2,178,353; 2,774,786;2,813,898; and 2,828,332.

A detergent composition prepared according to the present inventioncontains as essential ingredients (a) a detergent ingredient and (b) abuilder ingredient. In simplest terms, a composition can contain asingle detergent com pound and a single builder compound. On the otherhand, it frequently is desirable to formulate a detergent composition inwhich the detergent ingredient consists of mixtures of detergentcompounds selected from the foregoing classes. Thus, for example, theactive ingredient can consist of a mixture of two or more anionicdetergents; or a mixture of an anionic detergent and a nonionicdetergent; or, by way of anotehr example, the active detergent can be aternary mixture of two anionic detergents anda zwitterionic detergent.

The part of the complete formulation that functions as a builder canlikewise be composed of a mixture of builder compounds. For example, thebuilder compounds described herein can be mixed together with otherwatersoluble inorganic alkaline builder salts such as sodiumtripolyphosphate or potassium pyrophosphate or potassium pyrophosphatesor a water-soluble organic builder salt such as Water-soluble salts ofnitrilotriacetic acid, ethylenediaminetetraacetic acid,ethane-l-hydroxy-1,1-diphosphonic acid. Still further, the buildercomponent of a complete formulation can consist of ternary mixtures ofthese several types of builder compounds.

Water-soluble inorganic alkaline builder salts which can be used in thisinvention in combination with the novel oligomeric ester chaincondensates of ethane-l-hydroxy-1,1-diphosphonates are alkali metalcarbonates, borates, phosphates, polyphosphates, bicarbonates andsilicates. Ammonium and substituted ammonium salts of these materialscan also be used. Specific examples of suitable salts are sodiumtripolyphosphate, sodium carbonate, sodium tetraborate, sodium andpotassium pyrophosphate, sodium and ammonium bicarbonate, potassiumtripolyphosphate, sodium hexametaphosphate sodium sesquicarbonate,sodium orthophosphate and potassium bicarbonate.

Examples of suitable organic water-soluble organic alkaline sequestrantbuilder salts whichcan be mixed with the ester chain condensates ofethane-1-hydroxy1,1-diphosphonate compounds of this invention are alkalimetal (sodium, potassium, lithium), ammonium or substituted ammonium,aminopolycarboxylates, e.g., the above mentioned sodium and potassiumethylenediaminetetraacetate, sodium and potassiumN-(2-hydroxyethyl)-ethylenediaminetriacetates, sodium and potassiumnitrilotriacetates and sodium, potassium and triethanolammonium N-(2-hydroxyethyl)-nitrilodiacetates. The alkali metal salts of phytic acid,e.g., sodium phytate, are also suitable as organic alkaline sequestrantbuilder salts. Certain other organic builders which can be used inadmixture herewith are water-soluble salts ofethane-l-hydroxy-l,l-diphosphonic acid, methylene diphosphonic acid, andthe like.

The builder mixtures taught herein are highly eflicient, and, ingeneral, can be used to permit the attainment of equal detergency with asmaller total quantity of builder in relation to the total quantity ofdetergent ingredient.

The detergent compositions of the present invention can be formulatedand prepared into any of the several commercially desirable solid andliquid forms including, for example, granules, flakes, tablets, andWater-based and alcohol-based liquid detergents, emulsions and the like.According to one embodiment of the present invention, solid detergentcompositions are prepared containing a detergent ingredient (singledetergent or a mixture of detergents) and a builder ingredient (singlebuilder or a mixture of builders) in the by weight ratio (detergent tobuilder) of about 2:1 to about 1:10; and preferably from about 1:1 toabout 1:6. A special embodiment of this invention is a liquid detergentcomposition containing a detergent and a builder in the by weight ratio(detergent to builder) of 3:1 to about 1:10; preferably 2:1 to about1:3. Potassium salts are especially useful in liquid formulations due tothe increased solubility characteristics of potassium over sodium.

Liquid detergent compositions containing builders are usually waterbased or have a mixture of water and al cohol in the liquid vehicle.Such liquid vehicles can be satisfactorily employed in formulating acomposition according to the present invention. Accordingly, a sampleliquid detergent composition of this invention consists essentially of adetergent ingredient (a single detergent or a mixture of detergents) andan oligomeric ester chain condensate ofethane-l-hydroxy-l,l-diphosphonate containing builder ingredient (eitheras a single builder or in admixture with other builders), with thebalance of the composition to being a liquid vehicle such as Water or awater alcohol mixture, and the like.

The detergent compositions of the present invention provide best resultswhen used in a washing solution which has a pH in the range of fromabout 8 to about 12.

Within this broad range, it is preferred to operate at a pH of fromabout 8 to 11. The detergent and the builder can be formulated toprovide a pH in this range. Usually the detergent composiiton itself hasa pH in the range of 8 to 12. If desired, other alkaline materials canbe added to the complete formulation to provide a pH in the requiredrange. A preferred embodiment is to have the detergent compositionwhether in solid or liquid form provide a pH in the aforementionedranges at the usual recommended usage levels.

In a finished detergent formulation, other materials can be presentwhich make the product more effective or more aesthetically attractive.The following are mentioned by way of example. A water-soluble sodiumcarboxymethyl cellulose can be added in minor amounts to inhibit soilredeposition. Tarnish inhibitors such as benzotriazole orethylenethiourea can also be added in amounts up to about 3%.Fluorescers, and brighteners, enzymes, perfumes, coloring agents, whilenot per se essential in the compositions of this invention, can be addedin minor amounts. As already mentioned, an alkaline material or alkalisuch as sodium or potassium hydroxide can be added as supplementary pHadjusters. Other usual addi-.

tives include sodium sulfate, sodium carbonate, water, and

the like. Corrosion inhibitors are also frequently used. Water-solublesilicates are highly elfective corrosion inhibitors and can be added ifdesired at levels of from about 3% to about 8% by weight of the totalcomposition. Alkali metal, preferably potassium and sodium silicates,are preferred having a weight ratio of SiO :M O of from about 1.0:1 to2.8:1. (M refers to sodium or potassium.) Sodium silicate having a ratioof SiO :Na O of from about 1.611 to 2.45:1 is especially preferred.

In the embodiment of this invention which provides for a liquiddetergent containing a builder, a hydrotrope is desirable. Suitablehydrotropes are water-soluble alkali metal salts of toluenesulfonate,benzenesulfonate, and xylenesulfonate. Preferred hydrotropes arepotassium or sodium toluenesulfonates. The hydrotrope salt can be addedat levels up to about 12%. The hydrotrope functions as a solubilizingagent to produce a product which retains its homogeneity at a lowtemperature.

The following compositions, in which the percentages are by weight, willserve to illustrate, but not limit, the invention. Each of thecompositions in the following examples give in solution a pH within thedesired range of from about 8 to about 12.

EXAMPLE A A granular built detergent composition according to thisinvention has the following formulation:

Percent Sodium alkyl benzene sulfonate in which the alkyl is a straightchain dodecyl radical 18 Sodium oligomeric ester chain condensate ofethane-lhydroxy-l,l-diphosphonic acid having a molecular weight of1000-3000 50 Sodium sulfate 15 Sodium silicate (ratio of SiO :Na of2: 1) 7 Water 10 This built detergent composition is especially valuablefor laundering heavily soiled clothes.

The straight chain dodecyl benzene sodium sulfonate in the precedingcomposition can be replaced on an equal Weight basis by either branchedchain dodecyl benzene sodium sulfonate, sodium tallow alkyl sulfate,sodium coconut oil alkyl sulfate, sodium olefin sulfonate as de scribedin the specification derived from alpha olefins having an average of 14carbon atoms in the molecule, or a mixture of straight chain dodecylbenzene sodium sulfonate, and sodium tallow alkyl sulfate on an equalweight basis. Anionic detergents are preferred. The sodium builder saltcan be replaced by an ammonium, potassium, or lithium salt; a sodiumoligomeric ester chain condensate of ethane-l-hydroxy-l,l-diphosphonicacid having a molecular weight of 800-2500; a 1:1 mixture of sodiumtriployphosphate and a sodium ester condensate ofethane-l-hydroxy-l,l-diphosphonic acid having a molecular weight of800-2500; a 1:1:1 ternary mixture of sodium tripolyphosphate, sodiumnitrilotriacetate and sodium ester chain condensate ofethane-1-hydroxy-l,1-diphosphonic acid having a molecular weight of700-2200; potassium ester of chain condensate of ethane-l-hydroxy-1,1-diphosphonic acid having a molecular weight of 650- 2000; ammoniumester chain condensate of ethane-l-hydroxy-1,l-diphosphonic acid havinga molecular weight of 600-1900; or lithium ester chain condensate ofethanel-hydroxy-1,1-diphosphonic acid having a molecular weight of500-1600.

EXAMPLE B Another effective granular detergent composition has thefollowing formulation:

Percent Straight chain dodecyl benzene sodium sulfonate (anionicdetergent) 4 Sodium tallow alkyl sulfate (anionic detergent) 4 Dodecylmethyl sulfoxide 2 Hydrogenated marine oil fatty acid 2 The sodiumoligomeric ester chain condensate prepared by Example II above havingthe general formula given above in which n has a numerical value of 1-16and a molecular weight of 500-3000 60 Sodium silicate (ratio of SiO :NaO of 1.6:1) 10 Sodium sulfate 14 Water 6 In this example, the totalactive detergent of 10% can be totally the nonionic species. Inaddition, the 2% dodecyl methyl sulfoxide can be replaced by the productof a condensation reaction between dodecyl phenol and 5 moles ofethylene oxide per mole of dodecyl phenol, or by3-(dodecyldimethylamonio)-2-hydroxy propane-1- sulfonate.

The sodium salt of the builder can be added as the salt or it can bepresent as the free acid neutralized in situ to any salt form rangingfrom the monosodium or monopotassium salt to the fully neutralizedtetrasodium or tetrapotassium salt. The builder can be replaced with a1:1 equal Weight mixture of potassium-1,2-dicarboxy-2-hydroxy-1,2-diphosphonate and the builder prepared in Example II.

EXAMPLE C Another example of a granular detergent composition ofoutstanding efficiency:

Percent Straight chain tridecylbenzene sodium sulfonate 1 (anionicdetergent) 20 Sodium ester chain condensate of ethane-l-hydroxy-1,1-diphosphonic acid prepared in Example III having a numerical valuefor n of 1-16 and a molecular weight of 500-4000 49 Sodium silicate(ratio SiO :Na O of 2: 1) 6 Sodium sulfate 14 Water 11 'lhis detergentcompound is also referred to as linear tridecyl benzene sodiumsulfonate.

1 EXAMPLE D Toluene sulfonate 1.8 Sodium silicate (ratio of SiO :Na O of2:1) 8.0 Sodium sulfate 2.0 Diethanolamide of coconut fatty acid 1.9Benzotriazole .02

Balance to 100% water.

In this composition, the nonionic detergent can be replaced bytetradecyl dimethyl phosphine oxide, sodium-3- dodecylaminopropionate,sodium-3-dodecylaminopropanesulfonate, 3(N,Ndimethyl-N-hexadecylammonio)-propane l sulfonate or 3-(N,Ndimethyl-N-dodecylammonio)-2hydroxypropane-l-sulfonate. Twenty percentof the builder can be replaced with an equal weight replacement oftrisodium ethane-l-hydroxy-1,1-diphosphonate.

As mentioned above, one of the desirable properties of a buildercompound is the ability to sequester hardness minerals which may bepresent in water. The oilgomeric ester chain condensates of the presentinvention have especially unique sequestering properties. Foremost amongthese are their sequestering properties both in respect to theirefficiency in sequestering and also in respect to how tightly thehardness mineral, e.g., calcium, magnesium, iron and the like is boundby the sequestrant. These notable sequestering properties of thecompounds of the present invention are illustrated below by performing aSwatch-Dip test and also be a nephelometric caprate sequestering test.

The Swatch-Dip test demonstrates the relative sequestering ability of acompound in terms of how tightly calcium is bound by the sequestrant.This test involves a procedure employing a fabric-swatch impregnatedwith soap and an aqueous solution containing a predetermined level ofcalcium hardness minerals. The procedure involves preparing an aqueoussolution containing the hardness ions and dipping or immersing into thesolution a fabric-swatch which has been impregnated with a measuredamount of soap. The swatch remains in the solution for a predeterminedamount of time. A measurement is then made to determine the amount offree calcium which has been adsorbed by the fabric-swatch. The procedureis then repeated but with a predetermined concentration of a sequestrantcompound added to the aqueous solution containing the calcium ions.Measurements of calcium adsorbed on the swatch are again made andcomparisons drawn. Differences between the amounts of calcium adsorbedin tests with and without sequestrants are attributed to the ability ofthe sequestrant to sequester the calcium and thereby reduce the amountof free calcium ions available for adsorption by the immersedfabricswatch. A percentage is obtained in this manner which is referredto as percentage hardness retained by sequestrant.

By using this procedure comparisons were made between sodiumtripolyphosphate (STP), sodium ethylenediaminetetraacetate (EDTA), andthe following compounds which are representative of the compounds towhich the present invention pertains:

Oligomer Esters (A) sodium salt of an oligomeric ester chain condensateof ethane-l-hydroxy1,1-diphosphonic acid prepared above in Example 1 asfraction 1; molecular weight of 1000-3000.

Oligomer Ester (B) sodium salt of an oligomeric ester chain condensateof ethane-l-hydroxy-l,l-diphosphonic acid prepared above in Example 1 asfraction 6; molecular weight of 500-1600.

STP is widely recognized as a useful sequestrant compound and builder.EDTA is one of the most eflicient sequestrants known. The demonstrationdescribed above revealed surprisingly that the oligomeric ester chaincondensates of the present invention are superior to both STP and EDTAin several respects.

In interpreting the results of the Swatch-Dip test, a higher percentagevalue means that the sequestrant is able to bind calcium ions moretightly than a sequestrant which scores a lower percentage. It wasdiscovered that at an equal concentration of .06% in the solution theoligomeric ester chain condensate (A) above scored a percentage value ofabout 99%. The oligomeric ester chain condensate (B) above also scoredabout 99%. EDTA, as expected, received a corresponding high score ofabout 98-99%. By contrast, STP obtained a percentage value of only about86%. Both of the representative oligomer ester compounds of the presentinvention were able to retain their surprisingly high scores even at aconcentration range of sequestrant in the test solution of only about015%. EDTA, however, fell off drastically at a concentration ofsequestrant in the test solution below 04%. STP drops off in itssequestering properties rather markedly below a concentration ofsequestrant in test solution below .05%.

The useful sequestering properties of the oligomeric ester chaincondensates of the present invention are also demonstrable by anephelornetric caprate sequestering test. The testing procedure employedis that described by Irani and Callis, J. Physical Chemistry, 64, 1398(1960). The only modification is that caprate was used instead ofoxalate as the indicator of the nephelometric endpoint. In thisdemonstration the same two representative oligomeric ester chaincondensates were tested as described in conjunction with the Swatch-Dipdemonstration. Comparisons were made with STP. The relative efficiencyof each of the sequestrants (in grams of calcium per 100 grams ofanhydrous sodium salt were as follows.

The greater efiiciency of the representative compounds of the presentinvention as sequestering agents over that of ST? is apparent from theresults given in the preceding table. It is quite apparent that at pH 8STP had no measurable sequestering property. By the same token, both ofthe compounds representative of the present invention were capable ofsequestering larger amounts of calcium even at lower pHs of 8-9 than thebest score which STP obtained across the full range of pH tested.

The efficiency advantage which the builder compounds of the presentinvention provide over a standard commercially used builder such assodium tripolyphosphate is shown by the following demonstration.

A series of detergency tests was conducted which is referred to as afacial swatch test. This test involves a procedure of soiling a clothswatch with natural soil by attaching a swatch (about 5 inches by 5inches) to the plunger cup of an electric vibrator massager. Twoswatches are soiled from an individual subject by massaging the rightand left halves of the face respectively for one minute each. Theresulting soiled swatches are randomized into different groups tostatistically provide equal numbers of left and right samples. Theswatches are then washed, rinsed and graded and the cycle is repeatednine times. The washing step consists of laundering the soiled swatchesin an aqueous solution having a temperature of F., a pH of 10, andcontaining 7 grains hardness.

A mechanical washer is used which is equipped with an agitator and whichotherwise simulates an ordinary home washing machine. The detergentcompositions tested were comprised of an organic synthetic detergent ata concentration in the wash water of .03% and a builder at a usageconcentration of 03%, .04% and, in some cases, .06%. The oligomericester chain condensates which were selected as being representative ofthe present invention for purposes of this demonstration were thefollowing:

Builder No. (l) a sodium oligomeric ester chain condensate prepared asin Example I above and corresponding Fraction No. 1 (average molecularweight 800-2500).

Builder No. (2) a sodium oligomeric ester chain condensate prepared asin Example I above and corresponding to Fraction No. 2 (averagemolecular weight 800-2500).

Builder No. (3) a sodium oligomeric ester chain condensate prepared asin Example I above and corresponding to Fraction No. 3 (averagemolecular weight 700-2200).

Builder No. (4) a sodium oligomeric ester chain condensate prepared asin Example I above and correponding to Fraction No. 6 (average molecularweight 500-1600).

Following the washing of the soiled swatches, they were rinsed and driedand then whiteness measurements were made with a commercially availablephotoelectric reflectometer, i.e., a Hunter Color and Color Differencemeter manufactured by Henry A. Gardner Laboratory, Inc. This instrumentis designed to distinguish color differences and operates on thetristimulus colorimeter principle. According to this principle, a 45degree diffuse reflectance of an incident light beam on a test specimenis measured through a combination of green, blue and amber filters. Theelectrical circuitry of the instrument is so designed that lightness andchromaticity values for the test specimen are read directly. Thedeparture from white (TiO being taken as a standard white) of the testspecimen is calculated by introducing the lightness and chromaticityvalues so obtained into a complex formula supplied by the manufacturer.An evaluation of relative whiteness performance compared to a standarddetergent composition is thus obtained for the test formulations. A morecomprehensive description of this device and its mode of operationappears in Color in Business, Science and Industry by Deane B. Judd,pages 260-262, published by John Wiley & Sons, New York (1952).

The measurements obtained by the foregoing procedure are given below inthe table. The builder efliciency advantage becomes readily apparentfrom a consideration of these figures.

The synthetic detergent which was used in each of the followingevaluations at a concentration in the wash solutions of 03% was sodiumdodecylbenzene sulfonate, the dodecyl group being derived fromtetrapropylene.

TABLE II .03%, 04%, columnI columln .06%, column Builder compound III Inthe foregoing table, a statistically significant difference is .68.

It can be seen from Column I headed 03% that the builder compounds ofthe present invention in each instance surpassed the performance of STPby a significant difference. The builder compound identified under (2)in the table above and which was evaluated at .04% provided a builderperformance superior to that of STP at .03% as well as .06%. Moreover,it will be seen that the oligomeric ester chain condensate buildercompounds of the present invention all compare favorably with EDTA at06%.

In addition to the preceding performance evaluations, anotherdemonstration involves measuring cleaning, whiteness and whitenessmaintenance properties. For purposes of this invention, these terms havethe following meanings. The term cleaning identifies the ability of abuilt detergent composition to remove soil from soiled fabrics. In part,this applies to the removal of deeply embedded soil deposits such asoccurs, for instance, at the collars and cuffs of shirts and blouses.Whiteness is a more general term which identifies or represents ameasurement of the ability of a built detergent composition to whitenareas which are only slightly or moderately soiled. Whitenessmaintenance is a term which is used to identify the ability of adetergent formulation to prevent the soil which has been removed duringa normal washing cycle from being redeposited upon the fabrics duringthe remainder of the laundering process, e.g., washing and rinsing, etc.

More specifically, the surprising building ability of the oligomericester chain condensate builder compounds of the present invention wasdiscovered by Washing naturally soiled white dress shirts with detergentcompositions built with dilferent builder materials. Shirts withdetachable collars and cuffs were worn by male subjects under ordinaryconditions for a certain period of time. The collars and cuffs were thendetached and washed in an ordinary agitator type washing machine usingsolutions of the built detergent compositions being evaluated.

The washed and dried collars and cuffs were graded by means of a visualcomparison with other collars and cuffs which had been similarly wornand soiled but which were washed with a standard built detergentcomposition. The visual comparisons were made by a trained panel of fivepeople who were unfamiliar with any specific details and objectives ofthe tests. Their judgments were made independently.

Their visual judgments were expressed on a scale ranging from zero toten. This determination records only the relative cleaning performancegrades among the several compositions being evaluated. Zero on thecleaning grade scale represents a cleaning level obtained by washingwith water along, i.e., no detergent formulation. A value of tenrepresents the cleaning level of a specially formulated standardizeddetergent composition under optimum conditions. For purposes of thisevaluation, a value grade of five represents a level of cleaning that isconsidered satisfactory in household practice. The test described aboveemployed a detergent composition consisting only of an active detergentcompound and a builder compound.

For this demonstration the following compounds were selected as beingrepresentative of those provided by the present invention: a sodiumoligomeric ester described above as No. 1 having a molecular weight1000-3000; a sodium oligomeric ester described above as No. 2 having amolecular weight 800-2500; and a sodium oligomeric ester described aboveas No. 4 having a molecular Weight 500-1600.

In this evaluation comparisons were drawn between the builder compoundsof the present invention and trisodium methylenedi-phosphonate (MDP),tetrasodium ethylenediaminetetraacetate (EDTA) and pentasodiumtripolyphosphate (STP In order to obtain as accurate a measurement aspossible of the builder properties of each of the sample compounds, noneof the additives usually found in commercial detergent compositions wereused in this demonstration. By limiting the compositions to only twoingredients, i.e., a detergent and a builder, there is no interferenceor masking of the builder function. The concentration of the activedetergent in the wash solution was .03% by weight. The concentration ofthe builders in the wash solution was either .03%, .04% or .06% asindicated in the table below. These percentages correspond toconcentrations of .03, .04 and .06 gram per 100 ml. of water. Inaddition, at washing solutions containing 7 grains per gallon hardness,equivalents (CaCO were adjusted with sodium hydroxide to a pH 10. Thetemperature of the washing solution was 140 F. The laundering cycle wasminutes.

A difference in the cleaning grade scale of one unit represents asignificant difference. A housewife readily and consistently can see acleaning difference between two fabrics which have grades separated by amagnitude of about one unit.

In cleaning performance sodium tripolyphosphate, an excellent builder,when used at a concentration in solution of .06% attains a grade of 5.This same level of cleaning is obtained with only .03% (one-half theconcentration) of two of the representative builders of this invention,namely, a sodium oligomeric ester chain condensate ofethane-l-hydroxy-l,l-diphosphonic acid having a molecular weight of8002500, n=1l6, No. 1 above, and sodium oligomeric ester chaincondensate of ethane-l-hydroxy-l,l-diphosphonic acid having a molecularweight of 500-1600, 11:1-16, No. 4 above. In addition, builder No. 1above, sodium oligomeric ester chain condensate ofethane-l-hydroxy-l,l-diphosphonic acid having a molecular weight of10003000, at a concentration of only 03%, was graded 7.6 which is farsuperior to sodium tripolyphosphonate at .03% or .06% concentration.

EDTA, by comparison, at .03% scores only a .4 which is far inferior tothe builder compounds described herein. At a concentration of .06%, EDTAdid score 7.6 which again was only equal to the compound of the presentinvention when used at only one-half the concentration, i.e., .03%.

Sodium methylene diphosphonate (MDP) scored only 2.8 at a builderconcentration of 06%, again showing the general effectiveness andefficiency of the builder compounds provided by the present invention.

The collar and cuff samples washed in accordance with the precedingdiscussion were also graded for whiteness performance results.

The whiteness measurements were made on the backs of the cuffs with acommercially available photoelectric reflectometer, i.e., a Hunter Colorand Color Difference meter manufactured by Henry A. Gardner Laboratory,Inc. This instrument is designed to distinguish color differences andoperates on the tristimulus colorimeter principle. According to thisprinciple, a 45-degree diffuse reflectance of an incident light beam ona test specimen is measured through a combination of green, blue andamber filters. The electrical circuitry of the instrument is so designedthat lightness and chromaticity values for the test specimen are readdirectly. The departure from white (TiO being taken as a standard white)of the test specimen is calculated by introducing the lightness andchromaticity values so obtained into a complex formula supplied by themanufacturer. An evaluation of relative whiteness performance comparedto a standard detergent composition is thus obtained for the testformulations and interpolated into a 1l0 scale. A more comprehensivedescription of this device and its mode of operation appears in Color InBusiness, Science and Industry by Deane B. Judd, pp. 260262; publishedby John Wiley & Sons, New York (1952).

In this demonstration also the oligomeric ester chain condensate buildercompounds of the present invention were shown to be generally moreeffective and efficient than the other builders tested and mentionedabove.

The evaluation of whiteness maintenance capability of the respectivebuilders was performed by the following method. Unsoiled swatches ofcotton terry cloth were washed with the wash solutions obtained from thecleaning tests. In other words, the unsoiled swatches are added to thedirty wash water from the cleaning tests. The swatches are dried andthen the whitness thereof is measured by a Hunter Color and ColorDifference Meter following the same procedure described above. The soiladhering to the swatches is a relative measure of soil which has beenadsorbed from the washing solutions containing the aforementionedrepresentative builders. Factors are involved here other than theanti-redeposition characteristics of the built detergent composition. Itis, however, one way of demonstrating this property; and for showingrelative performance, the test is valuable.

As with the cleaning and whiteness evaluation, the oligomeric esterchain condensates of this invention were shown to be highly effectiveand performed on a parity with sodium tripolyphosphate.

The foregoing description of the present invention has been presenteddescribing certain operable and preferred embodiments. It is notintended that the invention should be so limited since variations andmodifications thereof will be obvious to those skilled in the art, allof which are within the spirit and scope of this invention.

What is claimed is:

1. A detergent composition consisting essentially of:

(a) an organic synthetic detergent selected from the group consisting ofwater soluble anionic nonionic, ampholytic and zwitterionic detergentsand mixtures thereof, and

(b) an oligomeric ester chain condensate ofethanel-hydroxy-l,l-diphosphonic acid having the formula wherein each Mis selected from hydrogen, alkali metal, ammonium, alkylammonium,hydroxyalkylammonium, the alkyl and hydroxyalkyl groups each having 1 toabout 4 carbons; R is hydrogen or acetyl; and n has a numerical value inthe range of 1 to about 16, the molecular weight of the condensatesbeing in the range of about 500 to about 4000; the proportion of saiddetergent to said oligomeric ester being in the range of from about 5:1to about 1:20, by weight.

2. A built detergent composition of claim 1 in which the proportion ofsaid detergent to said oligomeric ester is in the range of from about2:1 to about 1:10.

6. A detergent composition of claim 1 in which said oligomeric ester isan alkali metal salt.

4. A detergent composition of claim 1 in which the numerical value for nis from 2 to about 12 and the molecular weight is from 700 to about3000.

5. A detergent composition of claim 1 in which the detergent is ananionic detergent.

References Cited UNITED STATES PATENTS 3,400,148 9/1968 Quimby .252-152XLEON D. ROSDOL, Primary Examiner M. HALPE-RN, Assistant Examiner US. Cl.X.R.

